JPH06321191A - Power brake device for aircraft - Google Patents

Abstract

PURPOSE:To dispense with a hydraulic source device exclusive for power brake device, and reduce cost and weight by utilizing the fluid pressure in the main gear shock absorber of an aircraft as fluid pressure, in a power brake device for aircraft for braking wheels by the liquid fluid. CONSTITUTION:When a rudder pedal 14 is operated, each master brake cylinder 2, 3 for main pilot and sub-pilot is operated through an operating link 7 to generate each pressure. Since a power brake valve 5 is opened according to each pressure, the pressure from a brake pressure holder 15 communicating to a main gear shock absorber 19 is force-fed to each main wheel brake 10, 11, which is then braked. On the other hand, when the main gear shock absorber 19 is situated in the leg raising position, a switching valve 16 is operated to make the air pressure of the brake pressure holder 15 flow into a brake reservoir 1, and, further, since the operating oil of the brake reservoir 1 flows into the brake pressure holder 15 through a check valve 8, the operating oil of each main wheel brake 10, 11 is supplied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aircraft power brake device applied to main wheels of an aircraft.

[0002]

2. Description of the Related Art FIG. 2 is an explanatory view of a conventional power brake device for an aircraft used as a main wheel of a small commercial aircraft. In the figure, the power brake device is equipped with a hydraulic power source device 9 for driving the brake, and when the operator operates the rudder pedal 14 in the direction indicated by the arrow, the master for the forward pilot is operated via the operation link 7. The brake cylinder 2 or the master brake cylinder 3 for the co-pilot operates to generate pressure. This master brake cylinder 2, 3
The power brake valve 5 is opened according to the pressure of the above, and the pressure from the hydraulic power source device 9 is sent to the main wheel brakes 10 and 11 to obtain the braking force of the main wheels.

Since the accumulator 8 attenuates the pulsation of the hydraulic pressure generated by the hydraulic pump 9a of the hydraulic power source device 9 and supplies a steady pressure to the main wheel brakes 10 and 11,
Also, the hydraulic pressure is constantly stored, and the hydraulic pressure is immediately supplied to the main wheel brakes 10 and 11 as needed. When used in combination with the hydraulic power source device 9, the hydraulic power source device 9 is electrically driven. It is not necessary to continuously operate the motor 9b and the hydraulic pump 9a to maintain the pressure, and the electric motor 9b is driven only when the accumulator 8 becomes equal to or lower than the specified pressure, and when the accumulator reaches the rated pressure, the electric motor is driven. By automatically performing the intermittent operation to disconnect 9b, the electric motor 9b and the hydraulic pump 9a are downsized, and the hydraulic power source device 9 is downsized. The brake reservoir 1 supplies the hydraulic oil consumed between the master brake cylinders 2 and 3 and the power brake valve 5 and releases the pressure in the master brake cylinders 2 and 3 at the time of brake release into the brake reservoir 1. Is equipped with.
The anti-skid system consisting of the anti-skid controller 13 and the anti-skid sensor 12 has been recently installed in a small aircraft to facilitate the brake operation. The anti-skid sensor 12 monitors the tire slip condition, When a skid occurs, the power brake valve 5 operates in a direction to release the pressure by a signal from the anti-skid controller 13, and the skid is released by returning the pressure to the main wheel brakes 10 and 11 to the reservoir 9c of the hydraulic power source device 9. To do.

[0004]

As described above, the conventional power brake device for an aircraft requires the hydraulic power source device 9 regardless of whether or not the anti-skid system is installed, but in a small aircraft, the human power is required. It is common to use a control device by the electric actuator, and in the case of a manpower control device, a complicated hydraulic power source device is not particularly required, and an electric actuator or a simple hydraulic pressure is exclusively used for operating the flap and raising and lowering the landing gear. The source is equipped. These power sources are used only during takeoff and landing, so simple ON
It may be one that turns off. On the other hand, in the power brake device, the characteristics such as pressure pulsation and pressure drop in the hydraulic power source device 9 have a great influence on the braking characteristics thereof, and the hydraulic power source device 9 having good response performance that can correspond to the servo circuit such as the power brake valve 5 is provided. Therefore, a separate hydraulic power source device 9 must be provided exclusively for the power brake device, which is disadvantageous in terms of cost, weight, reliability and the like.

[0005]

The power brake device for an aircraft according to the present invention is intended to solve the above problems.
In a power brake device for an aircraft that brakes wheels by fluid pressure, a feature is used in which the fluid pressure in the main landing gear shock absorber of the aircraft is used as the fluid pressure.

[0006]

That is, in the aircraft power brake device according to the present invention, the fluid pressure in the aircraft main landing gear damping device is utilized as the fluid pressure in the aircraft power brake device that brakes the wheels by the fluid pressure. There is no need for a separate hydraulic power source device exclusively for the braking device.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory diagram of a power brake device according to an embodiment of the present invention. In the figure, the power brake device according to the present embodiment is used for the main wheels of a small commercial aircraft having a landing weight of about 8 tons, and the main gear shock absorber (oleos strut) is used instead of the conventional hydraulic power source device dedicated to the power brake device. ) Utilizing the air pressure inside 19, when the operator actuates the rudder petal 14 in the direction indicated by the arrow,
Through the operation link 7, the master brake cylinder 2 for the forward pilot or the master brake cylinder 3 for the first pilot operates to generate pressure. The power brake valve 5 opens according to the pressure of the master brake cylinders 2 and 3,
Brake pressure retainer 1 communicating with the main landing gear damper 19
The braking force of the main wheel brakes 10 and 11 is obtained by sending the pressure from 5 to the main wheel brakes 10 and 11. The brake reservoir 1 supplies the hydraulic oil consumed between the master brake cylinders 2 and 3 and the power brake valve 5 and releases the pressure in the master brake cylinders 2 and 3 at the time of brake release into the brake reservoir 1. Is equipped with. The anti-skid system consisting of the anti-skid controller 13 and the anti-skid sensor 12 is equipped to facilitate the brake operation. The anti-skid sensor 12 monitors the tire slip condition, and when the skid occurs, the anti-skid controller is used. The power brake valve 5 is actuated in the direction of releasing pressure by the signal from 13, and the skid is released by returning the pressure to the main wheel brakes 10 and 11 to the brake reservoir 1. In the figure, reference numeral 4 is a mixing valve, 6 is a parking valve, 7 is an operation link, 8 is a check valve,
Reference numeral 16 is an electromagnetic switching valve, and 19a is a main landing gear shock absorber device 19.
Is an air chamber, 19b is an orifice support tube, 19c is an orifice, 19d is a piston, and 19e is an axle.

In the main landing gear damper 19, the shape of the orifice in the throttle valve 19c, the amount of hydraulic oil, the characteristics depending on the air pressure to be enclosed, etc. are determined according to the load shared by the main landing gears and the specifications of the machine body. The pressure in 19a varies depending on the weight of the airframe, but in the case of a small aircraft, when the piston 19d of the main landing gear damper 19 is fully extended, the initial enclosed pressure is about 70 to 110 psi. 600-80 because the volume of the air chamber 19a is reduced by making a stroke
It rises to about 0 psi. The main wheel brakes 10 and 11 are operated after the main landing gears have touched down, but the air pressure inside the main landing gear damper 19 is approximately 500 psi, which is close to the pressure at rest on the ground due to the gliding. 1
Sufficiently satisfies the pressure required for 0 and 11. Therefore, in a small aircraft having a takeoff weight of 10 tons or less, the main wheels can be braked by the main wheel brakes 10 and 11 by using the air pressure in the main landing gear damper 19.

The master brake cylinders 2 and 3 generate pressures according to the operating force of the rudder petal 14, and the opening of the power brake valve 5 changes according to these pressures, so the pressure applied to the main wheel brakes 10 and 11 is increased. Is controlled to obtain a braking force according to the control of the operator. The operation of the main wheel brakes 10 and 11 is performed after the main wheels and the front wheels are in contact with the ground, and the air chamber 19a of the main landing gear shock absorber 19 at this time is
The pressure inside is about 600 psi, which is close to the pressure at rest on the ground. In addition, the main wheel brakes 10, 1
The pressure required for 1 is about 200 psi for a normal stop.
Approximately 400 psi in case of stoppage during takeoff abandonment (Rejected Take-Off). The brake pressure retainer 15 converts air pressure of about 600 psi in the main landing gear damper 19 into hydraulic pressure required for the main wheel brakes 10 and 11, and
It holds the amount of oil required for the main wheel brakes 10 and 11,
The amount of oil required for the main wheel brakes 10 and 11 is set on the safe side based on the number of brakes used in one flight.

Since the power brake valve 5 is closed when the main wheel brakes 10 and 11 are not used, the pressure in the brake pressure retainer 15 is maintained at the inlet of the power brake valve 5, but the master brake cylinder When the power brake valve 5 is opened with a few pressures, the pressure in the brake pressure retainer 15 flows into the main wheel brakes 10 and 11 to brake the main wheels. As for the pressure flowing into the main wheel brakes 10 and 11, the opening degree of the power brake valve 5 changes according to the pressure of the master brake cylinders 2 and 3, and the pressure of the main wheel brakes 10 and 11 is controlled. The hydraulic oil that has become unnecessary when the pressure is controlled by the power brake valve 5 is returned to the brake reservoir 1 through the return line. Further, when the operation of the main wheel brakes 10 and 11 is released, the main wheel brakes 10 and 1 are released.
The pressure in 1 returns to the brake reservoir 1.

During flight, the main landing gear shock absorber 19 is in the leg raising position and the piston 19d is in the most extended state, so the pressure in the air chamber 9a is about 70 psi, which is the same as the initial enclosed pressure. In order to replenish the hydraulic oil in the brake pressure retainer 15 used on the ground during this flight, the switching valve 16 is automatically moved when the main landing gear damper 19 is in the landing position.
Is activated to connect the brake pressure retainer 15 and the brake reservoir 1 to each other, and
When the air pressure of about 0 psi enters the brake reservoir 1 and pushes down the pressurizing piston of the brake reservoir 1, the hydraulic oil in the brake reservoir 1 is transferred to the check valve 8
So that the hydraulic oil in the brake pressure retainer 15 becomes a sufficient amount for operating the main wheel brakes 10 and 11 and can be used again when landing. Become. In this way, the hydraulic oil of the main wheel brakes 10 and 11 consumed by the operation of the main wheel brakes 10 and 11 on the ground is replenished immediately after the takeoff of the leg after takeoff, and the main wheel brakes 10 and 11 can always be operated. It has become. When the landing gear is lowered during landing, the landing gear signal is released, and at the same time, the switching valve 16 connects the main landing gear damper 19 and the brake pressure retainer 15 to the main wheel brakes 10 and 11 as shown in the figure. The pressure can be supplied, and at the same time as the ground contact, 60 is applied to the main wheel brakes 10 and 11.
A pressure of about 0 psi is generated in the brake pressure retainer 15. The switching valve 16 is electrically operated in sequence by an electric signal for raising and lowering the legs.

In the conventional power brake system for an aircraft, a hydraulic power source device is required regardless of whether or not the anti-skid system is equipped, but in a small aircraft, it is general to use a maneuvering device by manpower. In the case of a human-powered control device, a complicated hydraulic power source device is not particularly required, and an electric actuator or a simple hydraulic pressure source is exclusively provided for actuating the flaps and raising / lowering the landing gear. These power sources are used only during takeoff and landing, so simple ON-OFF operation is sufficient. On the other hand, in the power brake device, characteristics such as pressure pulsation and pressure drop in the hydraulic power source device have a great influence on the brake characteristics, and further, a hydraulic power source device having good response performance capable of supporting a servo circuit such as a power brake valve is required. Therefore, it is necessary to equip a dedicated hydraulic power source device for the power brake device, which is disadvantageous in terms of cost, weight, reliability, etc. By eliminating the complicated hydraulic power source device and utilizing the air pressure in the main landing gear damper 19, cost reduction, weight reduction, power saving, system simplification, and improvement of maintainability can be achieved in a small aircraft. .

[0013]

The power brake device for an aircraft according to the present invention is configured as described above and does not require a hydraulic power source device dedicated to the power brake device, so that cost, weight,
It is advantageous in terms of reliability.

[Brief description of drawings]

FIG. 1 is a system diagram of a power brake device according to an embodiment of the present invention.

FIG. 2 is a system diagram of a conventional power brake device.

[Explanation of symbols]

 1 Brake Reservoir 2 Master Pilot Cylinder for Forward Pilot 3 Master Brake Cylinder for Copilot 4 Mixing Valve 5 Power Brake Valve 6 Parking Valve 7 Working Link 8 Check Valve 10 Portside Main Wheel Brake 11 Starboard Main Wheel Brake 12 Anti-skid sensor 13 Anti-skid controller 14 Rudder pedal 15 Brake pressure retainer 16 Electromagnetic switching valve 19 Starboard main landing gear shock absorber 19a Air chamber 19b Orifice support tube 19c Orifice 19d Piston 19e Axle

Claims (1)

[Claims] 1. A power brake device for an aircraft that brakes wheels by fluid pressure, wherein the fluid pressure in a main landing gear shock absorber of the aircraft is used as the fluid pressure.